Mooring device for aircraft



abbot/"e1 8 amuamtoz W/mf - G. SMITH MOORING DEVICE FOR AIRCRAFT Fgled Feb 25, 1922 March 31, 1925.

Patented Mar. 31, 1925.

UNITED STATES PATENT OFFICE...

GEORGE SMITH, F BALTIMORE, MARYLAND, ASSIGNOR TO ELLICOTT MACHINE CORPORATION, OF BALTIMORE, MARYLAND, A CORPORATION OF DELAWARE.

MOORING DEVICE FOR AIRCRAFT.

Application filed February 25, 1922. Serial No. 539,110.

To all whom it may concern;

Be it known that I, GnoRen SMITH, a citizen of the United States, residin at Baltimore, in the State of Marylan have invented certain new and useful Improvements in Mooring Devices for Aircraft, of which the following is a specification.

This invention relates to mooring devices for air-craft, and particularly for dirigible balloons, of both rigid and non-rigid types.

The object of the invention is to relieve the envelope and frame work of the balloon of localized stresses.

The invention is particularly applicable to that type of mooring device ,in which a swiveling head is provided witha centering ring which receives the nose of the balloon and functions to maintain approximate alinement of the balloon, when the nose is held within the ring by means of a central mooring cable. j

When a balloon is moored tightly to a device of this class while a strong wind is blowing, the cable must be put under heavy tension merely to draw the balloon into light contact with the ring. If the wind thereafter fallsQthe draft of the balloon on the cable is lowered and the stress of the cable on the balloon is resisted by pressure of the ring against the balloon. In the case of gusty winds the condltion is even worse because of the repeated sudden shocks on the.

line of contact of the centering ring with the nose of the balloon.

In veering winds, also, the inertia of the swiveling head sets up heavy stresses which are resisted by the balloon at its lineof contact with the centering ring.

The present invention provides a combined centering and bufiing ring, which in its normal or unstressed condition ofiers a positive centering'action, and which is nevertheless capable of yielding easily in the direction of stress exerted by the cable. 1 In the preferred form, the centering ring is so mounted that its resistance to displacement rises at an ever-increasing rate as the displacement progresses.

A practical embodiment of the invention is shown in the accompanying drawing, in which- Fig. 1 is a front view of the structure,

Fig. 2 is a side view of the same,.partly in section,

Fig. 3 is a fragmentary section on an enlarged scale showing how the bufling. ring is mounted.

The usual mast is shown at 5. At the top' of mast 5 is a head 6 mounted to swivel on a vertical axis, and provided with a guide sheave 7 and trunnions 8. Mounted to rock in a vertical plane on the trunnions 8 is a yoke 9 provided with counter weights 10 at one end and a bearing 11 at the other. A-

passage 12 for the mooring cable extendsv longitudinally through the bearing 11.

A hub 13 rotatable on bearing 11 carries a frame of generally conical outline, consisting of a circular girth 14, Spreaders 15. and braces 16 for the spreaders- The parts so far described follow, in their general form and arrangement, established practise. Instead of mounting an annular pad directly on the girth 14, as has been the usual practise, I mount the pad on a bufling ring, which is movably supported in a special manner on the girth 14.

This bufling ring is shown at 17 and carries an annular pad 18. It is held by a plurality of radially arranged and hence mutually opposed tension devices indicated generally by the numeral 19, eight being shown in the drawing. Each of these tension devices 19 is pivotally connected tothe ring 17 at 20 and to the girth 14 at 21.

Asis best shown in Fig. 3. the tension device is of that type which acts when in tension to place a coil spring under compression. A cylindrical shell 22 pivotally connected at 21 to girth 14houses a plunger 23 having a head 24. The plunger 23 is pivotally connected at 20 to ring 17. A coil spring 25 confined between head 24 and the end of shell 22 resists the withdrawal of plunger 23.

In the normal position of the parts, shown in Figs. 2 and 3, the axes of the tension devices 19 are all in one plane. The springs 25 are only slightly stressed, and act to hold the heads 21 against stops 26. This ensures accurate and positive centering of ring 17, the spring devices then acting as struts.

The outline of the nose of the balloon is shown in broken lines at 27 and the balloon is moored by a bridle 28 (also shown .in

broken lines), to which the mooring cable 29 is attached. The cable passes through the tubular" guide 12, over sheave 7 and down through the hollow mast 5 to any suitable Windlass (not shown). As ordinarily conslight spring resistance. 25-

structed such'windlasses include a spring device to maintain the cable under tension and the invention is particularly, thou h not exclusively, adapted to use with win lasses so equipped.

If, in the case where a Windlass is used not provided with a spring device, the balloon is moored to the device in a heavy wind, the relatively heavy stress on the cable will, when the wind falls, draw the nose of the balloon slightly inward.- If a sprin device is used in the Windlass the stress on t e cable can be relieved only by considerable movement. In any event the ring 17' and pad 18 move bodily inward, relieving the stress on the balloon. If the balloon swings in a. veering wind, the ring 17 will yield to accommodate the motion of the balloon until the inertia of the supporting structure is overcome.

The arrangement of the tension devices is such that the ring 17 moves inward for a considerable distance against a relatively This resistance increases at first at a very slow rate, because the tension devices are acting very nearly in the plane of the ring, and because during the first portion of the motion of the ring the springs 25 are only slightly stressed. In other words, the resistance to the motion of the ring is slight at first and for a considerable distance increases only at a very moderate rate. As the ring is progressively displaced, the resistance increases at an ever increasing rate and finally rises at a very rapid rate because of the fact that the spring devices have an ever increasing component in opposition to continued motion, a condition which results not only in an increased efiective resistance, but in a rapidly increasing stress upon the springs 25. This arrangement, therefore, has particular advantage arising from the sition to the movement of the bufling ring.

What is claimed is 1. The combination with a mooring device for air-craft, including a frame, and a cable adapted to be attached to the air-craft and serving to draw the air-craft toward the mooring device; of a bufiing member resiliently mounted on said frame in position to engage said air-craft at aplurality of points aft of the nose thereof, said bufier having substantial range of movement in the direction of draft of said cable, different portions of said bufl'er being free to move unequally in such direction in response to unequal pressures exerted thereon by an aircraft.

2. The combination with a mooring device for air-craft, including a cable adapted to be connected to the air-craft and serving to draw the same toward the mooring device; of a bufiing member movably mounted relatively to said mooring device and adapted to nature of the spring oppo-.

engage an air-craft connected to said cable; and resilie t means operably connected to said bufling member and opposing motion thereof in the direction of the draft of said cable, said resilient means being constructed and arranged to offer relatively slight resistanceto such motion throu h a considerable range thereof. with a rapidly increasing resistance near the end of its motion.

3. The combination with a mooring device for air-craft. including a cable adapted to be attached to the air-craft and serving to draw the same toward the mooring device; of a bufling member movably mounted relatively to said mooring device and adapted to engage an air-craft connected to said cable;

and a plurality of tension spring devices normally acting radially substantially in a common plane and serving to position said bufiing member, said spring members exerting a slight resistance to the displacement of said bufiing member while the same is at or near its normal position, but exerting a rapidly increasing resistance when said buffing member is substantially displaced.

4. In a mooring device for air-craft, the combination of a support; a frame mounted on said support and capable of movement thereon to conform to the direction of air currents; a cable guided by said support and adapted to be attached to the air-craft to be moored and to draw said craft toward said support; a yielding spring mechanism mounted on said frame; and a combined centerin and buifing member mounted on said spring mechanism, adapted to engage said craft adjacent the point of attachment of said cable thereto and serving to maintain alinement of the craft with said frame and to receive the draft of said cable.

5. In a mooring device for air-craft, the combination of a support; a frame mounted on said support and capable of movement thereon to conform to the direction of air currents; a cable guided by said support and adapted to be attached to the nose of the air-craft to be moored and to draw said craft toward said support; a centering ring for engaging said air-craft aft of said nose and adapted to maintain the alinement of said air-craft while receiving the draft of said cable exerted thereon through said air-craft; and a plurality of radially arranged spring devices supporting said ring in said frame, and capable of yielding to allow said ring to move under the draft of said cable.

6. In a mooring device for air-craft, the combination of a support; a frame mounted on said support and capable of movement thereon to conform to the direction of air currents; a cable guided by said support and adapted to be attached to the nose of the air-craft to be moored and to draw said craft toward said support; a centering ring for engaging sa d air-craft aft of said nose and adapted to maintain the alinementof said air-craft while receiving the draft of said cable exerted thereon through said air-craft; a plurality of radially arranged sprin devices supporting said ring andcapab e of yielding in tension to allow the. centering ring to yield to the draft of the cable; and a series of stops servin positively to support said ring in said rame, in its normal position.

7. In a mooring device for air-craft, the

combinationof a support; a frame mounted on said support and capable of movement thereon to conform to the direction of air currents; a cable guided by said support and adapted to be attached to the nose of the air-craft to be moored and to draw-said craft toward said support; a centerin ring for engaging said air-craft aft of sai nose and adapted to maintain the alinement of said air-craft while receiving the draft of said cable exerted thereon through said air-craft; and a pluralit of tension spring devices supporting sai ring and each including a positive stop serving to limit the contractile movement of such spring device, whereby the ring is positively posltioned in its normal sition.

8. n a'mooring device for air-craft, the

gaging said air-craft aft of said nose and adapted to maintain the alinement of said air craft while receiving the draft of said cable exerted thereon through said air-craft; and a yielding spring support for said centering ring, which near its normal position exerts slight resistance to the displacement of said ring in the direction of draft of said cable. v I

In testimony whereof I have signed my name to this specification.

GEORGE SMITH. 

